View Full Version : Final jet kit settings for '95 kat 600

03-08-2007, 09:53 PM
I've seen a lot of questions about jet kits on here lately, and it just so happens that I just finished painting, jetting, and overall rebuilding a '95 katana. I didn't get far into the motor, but just about everything else on the bike has been rebuilt.

Anyways, the bike is totally stock EXCEPT a full Yoshimira exhaust system, headers and can.

I purchased a factory pro jet kit, thinking that I would need it, and of course put the largest jets in (117.5) because, hey, it has a full system right?

Wrong. The top end was brilliant, it idled ok, but the midrange from 5-7000 RPM was totally dead. I couldn't lean it out enough, it was always too rich with any needle setting.

So I went to the 115 main jet settings, and again, great on top, idle was a bit lean (had fuel screws 4 turns out, still not rich enough), way too rich on the midrange.

Finally, I put everything stock back in it, 112.5 mains, stock needles, but a 35 idle jet (stock is 32.5). It now idles and runs great. There is a very, very slight dead spot around 6000 rpm, but I don't want to experiment any more with the aftermarket needles. I figured i'd put them up on Ebay or something, obviously my bike doesn't want a jet kit.

Anyways, I just thought i'd share. With aftermarket filters or something, maybe it does need a kit. But this particular bike, the exhaust apparently didn't lean it out enough to need bigger jets. I hope to post picks soon, the paint turned out great.

Thanks for all who offered advice.

03-09-2007, 03:43 AM
DYNO/EGA that bad boy :-s ? I THOUGHT I had mine close to perfect a couple years ago ..... until I did the EGA run :smt011 :lol: . It was WAAAAAAAAY off , but it FELT pretty damned close . I'm just sayin' ....

03-09-2007, 06:40 PM
Ya I thought about that too. I don't have easy access to a dyno, but the shop I work at does have an EGA machine. I'll hook it up there whenever I get the chance.

Even if the mixture is off though, NONE of the settings on the jet kit worked, it was almsot un-drivable with some of them. I'll probably end up just leaving it how it is.

Also, as my girlfriend is riding this bike (her second bike), flawless throttle response is far more important to me than outright power. I don't want her to have to deal with a flat spot at 5k rpm....I'd rather her just be down 5 hp and have a bike that carburates well. Beginners can get into trouble if a bike doesn't do what it's told....

03-10-2007, 02:55 AM
Yeah , what I hated most was getting the pilots "right" , too len and it'd "jerk" at part throttle sneaking it on mid-corner . Too rich , and besides fouling plugs , it was "soft" . :dunno:
BTW , EGA , if you can take it WITH you , you'll need to check it under load . In neutral won't tell you much other than your idle circuit :thinking .But he11 , if it feels good , and plugs look right .... :dunno: